Document scanner

ABSTRACT

A document scanner ( 10 ) includes an input tray ( 20 ) for holding documents ( 11 ). An input image capture device ( 30 ) captures at least a portion of the images of documents in the input tray. An image processor ( 65 ) determines characteristics of documents in the input tray, and the documents are processed based on the characteristics. At least one characteristic is document length ( 70 ), or width ( 80 ), or position ( 170 ), or other characteristics. An ultrasonic zone ( 160 ) detects the documents; and the ultrasonic zones are enabled or disabled in at least one location down the document based on at least one characteristic.

CROSS REFERENCE TO RELATED APPLICATIONS

Reference is made to commonly-assigned copending U.S. patent applicationSer. No. ______ (Attorney Docket No. K000456US01NAB), filed herewith,entitled DETERMINING DOCUMENT CHARACTERISTICS PRIOR TO SCANNING, byPultorak; U.S. patent application Ser. No. 12/839,476, filed Jul. 20,2010, entitled METHOD FOR DOCUMENT SCANNING, by Schaertel et al.; andU.S. patent application Ser. No. 12/839,471, filed Jul. 20, 2010,entitled A DOCUMENT SCANNER, by Schaertel et al.; the disclosures ofwhich are incorporated herein.

FIELD OF THE INVENTION

This invention relates to extracting properties of the document fed to ascanner from an input tray, before the document passes scanning camerason a transport path.

BACKGROUND OF THE INVENTION

A document scanner moves a document through a transport path and createsan image of the document as it moves. The processor memory for thedocument scanner must have preset document characteristics and theoperator must select functions and features to accommodate the specificrequirements for a particular document. Alternately, the scanner maydefault to less efficient settings that will process all documents sincescanners are not typically programmed with specific requirements on adocument-by-document basis.

The preset characteristics, features, and functions are a product ofdocument characteristics, such as size, weight, texture, and specificapplication requirements such as resolution, and imaging mode; forexample color, simplex, or duplex. In a document scanner, the documentsto be scanned may vary by size, weight, color content, physicalcondition, or other characteristics, which may require different scannerfeatures to be enabled or operator actions to be employed for the mostoptimal and efficient mode of operation. Prior knowledge of these manydifferent document attributes can enable the proper selection of scannerfeatures to improve the efficiency of the scanning process or enableother features which may provide specific applications required by aparticular type, style, or size of document.

Prior knowledge of the documents physical condition can also promptimmediate action from the operator to protect the document or scanner orallow other features within the scanner to perform more reliably. Thereis a need, therefore, for detection of document characteristics prior tothe document entering the transport path.

SUMMARY OF THE INVENTION

Briefly, according to one aspect of the present invention A documentscanner includes an input tray for holding documents. An input imagecapture device captures at least a portion of the images of documents inthe input tray. An image processor determines characteristics ofdocuments in the input tray, and the documents are processed based onthe characteristics. At least one characteristic is document length, orwidth, or position, or other characteristics. Ultrasonic zone detectsthe documents; and the ultrasonic zones are enabled or disabled in atleast one location down the document based on at least onecharacteristic.

The invention and its objects and advantages will become more apparentin the detailed description of the preferred embodiment presented below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-section view from the side of a document scanner whichillustrates the various parts of the scanner related to the presentinvention.

FIG. 2 is a perspective view of the scanner and illustrates varioustypes of documents.

FIG. 3 is a top schematic view of a documents width, length and positionin a transport relative to sensing zones as the document travels throughthe transport.

DETAILED DESCRIPTION OF THE INVENTION

The present invention will be directed in particular to elements formingpart of, or in cooperation more directly with the apparatus inaccordance with the present invention. It is to be understood thatelements not specifically shown or described may take various forms wellknown to those skilled in the art.

FIG. 1 is a side cross-sectional view of a document scanner 10. Theillustration shows the input tray 20 and input tray camera or imagecapture device 30. A typical scanner also has a transport mechanism formoving documents through the scanner and an output tray for collectingdocuments as well as other components that makeup a document scanner.

As shown in FIG. 1, documents 11 are first placed in the input tray 20of the scanner. Imaging capture device 30 captures an image of the topdocument on the stack of documents 11. The document image is capturedboth statically and dynamically as it begins to move forward into thescanner by the feed roller 40 and separation roller 41. As frames ofimage data are captured, they are transmitted to be processed by animage processor shown schematically as image processing block 60.

The image processing block 60 processes the image data, to determinedocument characteristics such as document content, document condition,the desired information to be extracted and saved from the document.These characteristics will enable a particular feature or operation ofthe scanner based on the document content or condition. The document isprocessed based on the document characteristics.

Some of the document characteristics that are important in processingthe document is the document length 70 or width 80 shown in FIG. 2. If ashort document is detected the master image buffer (not shown) size isreduced. If a short document is detected the feed roller 40 may also bestopped to prevent jams. For a longer document, the feed rollercontinues to run which will reduce feed roller wear.

An important feature related to document length 70, width 80, andposition 170 as shown in FIG. 3, is the enabling and disabling ofindividual ultrasonic sensing zones 160, which can be found in adocument scanner. If the document 11 is of a size or position in theinput tray 20 such that the edge of the document may cause a falsemultiple detection by crossing over a portion of an ultrasonic sensingzone 160, the ultrasonic sensing zone 160 can be disabled for thatparticular document 11 and re enabled for the next document without theintervention of an operator. Also if the length 70, width 80, andposition 170 of the document 11 are known, all the ultrasonic sensingzones 160 can be enabled such that any zone that is sufficiently coveredwill detect a potential multiple document. An image of the documentlength 70, width 80, and position 170 can be determined by use of animaging capture device 30 or other sensing apparatus. Once the edges ofa document 11 have been detected by an imaging capture device 30, orother sensing apparatus, this information can then be transmitted to aprocessor 65 to determine the length 70, width 80, and position 170 ofthat document 11 in the input tray 20.

Another scanner feature related to length and width includes sorting thedocument on exit from the scanner. For example, if the document is acheck 90. The document may also be checked for compatibility with thescanner. Controlled output stacking 100 shown in FIG. 1 may be adjustedfor higher throughput, or a document gap 110 may be adjusted accordingto document length.

An important document characteristic is orientation. Detection of thedocument orientation as portrait or landscape, relative to the directionof document travel, will be used to improve the performance of the autoorientation feature. Using document width or location of the document inthe input tray 20, is used to improve the document locate function.

Color or lack thereof within a document will be determined to set theappropriate color mode for image capture. The document configuration mayalso be detected, for example, if a document has stick on labels 140applied to them or if the document is an envelope 142. The ultrasonicdetection 135 can tell where in the document to ignore the signal duringthe time the sticky label is passing through the ultrasonic sensingzones 160 or turn off the sensing zones 160 for an envelope. Stick onlabels 140 are detected based on color. The results are used to disableultrasonic sensing in the area of the label.

Content within the document will be used for line or form detection.This enables the processor 65 to determine whether to capture the imageor not and what processing may be required for the image data ifcaptured. Patches and barcodes will be detected and read for theprocessor to take the appropriate action. Detection of postage stamps144 or envelopes 142 is used by the processor to adjust scanneroperation.

Document content is processed using optical character recognition (OCR)to detect a predetermined word, detect and interpret magnetic characterink, photographs, text or graphics. The processor then modifies scannerfunctions, for example, disabling automatic orientation when no text ispresent. Money may also be detected and counted.

Document content is also used to detect checks 90 and documentresolution. The processor uses this information to adjust scannerfunctions such as setting the image capture mode.

A document characteristic useful for scanner processing is a foldedcorner or torn portion of the document. If those defects are detectedthe transport will be stopped and the operator will be alerted to thiscondition. Holes 82 in the document will be detected by the input imagecapture device 30 and ignored by the machine control function 120 of thescanner. Wrinkles in the document, if detected, causes processor tooptimized parameters for sonic 130 or ultrasonic 135 detection. Anotherdetectable characteristic is a staple, paperclip, or rubber band on thedocument. When detected the processor stops the transport and theoperator is alerted of the condition. Tape located on a document may bedetected and is a possible indication of a fraudulent document.

Imaging of the input tray 20 area detects the presence of documents 11or a batch box 12. Once documents are detected, the number of documentscan be determined. The absence of documents in the input tray will bedetected. Orientation or location of the documents detected indicatesdocument skew and location. This information enhances the performance ofautomatic orientation. The transport may be stopped and the operatoraltered to conditions that adversely affect operation of the scanner.

Imaging of the documents 11 will be used to detect dual shadows 150which may indicate a multi-feed. No movement of the documents mayindicate a misfeed.

Imaging of the input area 13 and processing of the image data willdetermine characteristics of the input area whereby side guide 15location can be determined. Correct side guide location will bedetermined with regard to the documents 11 in the input tray 20.

The invention has been described in detail with particular reference tocertain preferred embodiments thereof, but it will be understood thatvariations and modifications can be effected within the scope of theinvention.

PARTS LIST

-   10 scanner-   11 documents-   12 batch box-   13 input area-   15 side guide-   20 input tray-   30 imaging capture device-   40 feed roller-   41 separation roller-   60 image processing block-   65 processor-   70 document length-   80 document width-   82 holes-   90 check-   100 controlled output stacking-   110 document gap-   120 machine control function-   130 sonic detection-   135 ultrasonic detection-   140 stick on label-   142 envelope-   144 postage stamp-   150 dual shadows-   160 ultrasonic sensing zones-   170 position

1. A document scanner comprising: an input tray for holding documents;an input image capture device for capturing at least a portion of imagesof documents in the input tray; an image processor for determiningcharacteristics of documents in the input tray; wherein said documentsare processed based on said characteristics; wherein at least onecharacteristic is document length or width or position or othercharacteristics; ultrasonic zone for detecting the documents; andwherein the ultrasonic zones are enabled or disabled in at least onelocation down the document based on the at least one characteristic. 2.The document scanner as in claim 1 wherein a master image buffer isreduced for short documents.
 3. The document scanner as in claim 2wherein a feed roller is stopped on detection of short documents toprevent jams.
 4. The document scanner in claim 1 wherein said capturedevice is a linear sensor.
 5. The document scanner as in claim 1 whereincharacteristics comprise: notes or labels adhered to a document.